1. Field of the Invention
The invention concerns an apparatus for selecting and feeding weft yarns to an insertion device of a weaving machine, in which at least one weft feeder is displaceable between a rest position and a feed position by means of an eccentric drive having its own drive motor.
2. Description of Related Art
An apparatus which selects and feeds weft yarns to an insertion device of a weaving machine, and which has at least one weft feeder for feeding a weft and guided in its longitudinal direction, is shown in European published patent application EP 0 362 089 A1. In this apparatus, the rod- or needle-shaped feeders are supported in longitudinally displaceable manner in two longitudinal guides and are acted upon by rockers having a first end which is stationary and a second end which engages the feeders between longitudinal guides. The rockers are moved by actuation rods, first ends of which engage a central portion of the rockers and the other ends of which are connected to an eccentric drive which includes a drive motor, in particular a stepping motor. The excursion of the eccentric drives is transformed by the rockers, as a result of which the feeders move over a distance between their rest and feed positions which is about twice the excursion.
In another apparatus, disclosed in European published patent application EP 0 478 986 A1, displaceable yarn feeders are affixed to a toothed belt on alternating sides from the rest to the feed position. The toothed belt runs around a reversing wheel and around a drive wheel which has been actuated by an electric motor into a reciprocating motion.
Other apparatus for selecting and feeding wefts to an insertion device of a weaving machine are described in U.S. Pat. Nos. 4,964,443 and 4,781,226. In the apparatus described in the two U.S. patents, the feeders are actuated from the central machine drive by the intermediary of transmission means.